ICD-10-CM 2027 diagnosis code
I82.421Acute embolism and thrombosis of right iliac vein
I82.421 is a valid, billable ICD-10-CM code for acute embolism and thrombosis of right iliac vein. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About I82.421
I82.421 is the ICD-10-CM diagnosis code for acute embolism and thrombosis of right iliac vein. It belongs to category I82 (other venous embolism and thrombosis), block I80-I89 (diseases of veins, lymphatic vessels and lymph nodes, not elsewhere classified) and chapter 9 (diseases of the circulatory system). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within I82.42 (acute embolism and thrombosis of iliac vein), I82.421 is specifically for acute embolism and thrombosis of right iliac vein. Related codes cover left iliac vein (I82.422), bilateral (I82.423) and unspecified iliac vein (I82.429).
Code first venous embolism and thrombosis complicating: abortion, ectopic or molar pregnancy (O00-O07, O08.7) and pregnancy, childbirth and the puerperium (O22.-, O87.-).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
In MS-DRG v44.0, it is part of the grouping logic for DRG 299 (Peripheral Vascular Disorders with MCC, relative weight 1.5842), DRG 300 (Peripheral Vascular Disorders with CC, relative weight 1.0464) and DRG 301 (Peripheral Vascular Disorders without CC/MCC, relative weight 0.7133), in MDC 05 (Diseases and Disorders of the Circulatory System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Before ICD-10, this condition was coded in ICD-9-CM as 453.41 (acute venous embolism and thrombosis of deep vessels of proximal lower extremity).
Notes that apply from higher levels
Instructions written at a parent level also apply to I82.421.
› From I82 Other venous embolism and thrombosis
Broader instructions also apply from Chapter 9: Diseases of the circulatory system.
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 05 · Diseases and Disorders of the Circulatory System
ICD-9-CM equivalent
Converter →- 453.41Acute venous embolism and thrombosis of deep vessels of proximal lower extremityapproximate
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about I82.421
Is I82.421 billable?
- Yes. I82.421 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can I82.421 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict I82.421 as a principal diagnosis.
Is I82.421 a CC or MCC?
- I82.421 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.
What DRG does I82.421 group to?
- I82.421 is used in the MS-DRG v44.0 logic for MS-DRG 299 (Peripheral Vascular Disorders with MCC), MS-DRG 300 (Peripheral Vascular Disorders with CC) and MS-DRG 301 (Peripheral Vascular Disorders without CC/MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.
What is the ICD-9 code for I82.421?
- The CMS General Equivalence Mappings map I82.421 to ICD-9-CM 453.41.